The present invention relates to vending machines and, more particularly, to electronically controlled vending machines.
A wide variety of vending machines are in common use today, the majority of which are basically mechanical devices. When the proper amount of change has been deposited, a group of actuating levers become operable. Pulling or depressing a lever causes an article to be released from the corresponding receptacle and the article typically falls into an exposed tray.
Some machines that are used to dispense a large variety of products, particularly cigarette vending machines, utilize electric switches each connected to a solenoid that releases products from a particular receptacle. An exemplary solenoid-operated, article-releasing mechanism is described in U.S. Pat. No. 3,722,745.
Vending machines of conventional construction tend to become highly complex as additional functional capabilities are added. Examples of such added capabilities are provisions for dispensing different articles at different prices, provision for preventing more than one article releasing mechanism from being operated at a time and provision for preventing the machine from collecting money when empty.
A common problem with existing vending machines is that they sometimes collect a would-be purchaser's money without dispensing the product. Not only does the potential customer avoid use of the machine in the future, but acts of vandalism may be committed against the machine by an individual who believes he has been cheated.
A common provision for avoiding the collection of a would-be purchaser's money if no product is dispensed is an escrow chamber positioned above the bank of the machine. When coins are deposited, they fall into the escrow chamber where they are held until the product has been dispensed, at which time they fall into the bank. If no product is dispensed because, for example, the machine is empty, the money can be returned since it remains segregated in the escrow chamber.
Previously known mechanisms of this type are not, however, entirely satisfactory because they are built on the assumption that if the releasing mechanism goes through a complete cycle of operation, then an article has been dispensed. In some instances, the product becomes jammed in the machine and is not actually dispensed. In other instances, the machine may fail to detect that a receptacle is empty, allowing the releasing mechanism to operate and causing money to be collected from the escrow chamber even though no article has been dispensed.
It is an objective of the present invention to provide a vending machine that it relatively simple, compact and inexpensively manufactured but overcomes the above-mentioned operational disadvantages of conventional machines.